A control system has been proposed to use a mobile communication terminal such as a smartphone or a tablet computer as a controller for remote control of various electric appliances such as a TV set and an air conditioner placed in home.
When the mobile communication terminal is used as the controller, there is a need to limit a time period when the mobile communication terminal is available as the controller. For example, in a hotel or a condominium, it is convenient to use the mobile communication terminal of a guest as the controller for devices in a guest room such as a lighting device and an air conditioner only in a limited time period from a check-in to a check-out of the guest.
Simply providing the mobile communication terminal with the functions for using the mobile communication terminal as the controller, however, may cause a problem that the mobile communication terminal of the guest may be operated as the controller even after the check-out. For example, after a check-in of a next guest, the devices in the guest room may be subjected to control different from the next guest's intention.
Accordingly a technique of allowing the mobile communication terminal to be used as the controller only temporarily has been demanded. This problem is not limited to accommodation facilities but may also arise in any case using the mobile communication terminal of each user as the controller in theme parks and playgrounds.